Photoelectric tube



July 25 1950 o. T. MOILVAINE PHOTOELECTRIC TUBE Original Filed Sept. 9, 1944 arwe/vvto t- Oran T M iZ/l/a/Ima M Sum/wa Patented July 25, 1950 UNITED STATES PATENT OFFICE I 2,516,784 I PHO'I'OELECTRIC TUBE Oran T. Mcllvaine, St. Charles, 111. 7 Original application September 9, 1944, Serial No.

553,411. Divided and this application July 29, 1948, Serial No. 41,383

10 Claims. 1

This application is a division of my prior application filed September 9, 1944, Serial No 553,411 now Patent 2,451,400.

This invention relates to improvements in photo-electric tubes.

It has been customary heretofore to construct photo-electric tubes with anodes and cathodes, which are sometimes arranged in multiple in a single envelope, but this has involved multiplying both the anodes and cathodes, whereby a single anode would be arranged in association with a single cathode surface. Where the cathode surface is extended appreciably, this causes the electrons emitted from the cathode to travel in converging or diverging directions toward the anode, whereby such arrangements cannot be utilized to advantage in transmitting intelligence, photographic or code arrangement of dots, or for causing illumination of a bank of lights in a particular code or series, such as is often desired. These arrangements have heretofore required separate photo-electric cells for each point of light or other element to be reproduced or transmitted, which has made it impractical to transmit fine detail in pictures or to depict these on a bank of lights.

The object of this invention is to improve the construction of a photo-electric tube for this purpose, to enable it to be used for the difierent applications mentioned, one tube replacing the multiplicity of tubes required heretofore which, nevertheless, makes possible the transmission of pictures of fine detail in a more practical manner than has been possible with the multiplicity of photo-electric tubes as required heretofore.

This object is accomplished by utilizing a plurality of anodes associated with a single cathode, so arranged that the electrons emitted from the cathode surface will travel substantially in parallel directions to the adjacent anodes, whereby the electrons from a particular portion or spot on the cathode will go to a certain anode directly opposite this spot or portion. By this means any picture or pattern of shadow put on the cathode will cause the corresponding group of anodes to receive selectively the emission, and by arrangtheir association with a cathode whereby the electrons travel in parallel relation from the cathode surface to the corresponding anodes.

I have shown one embodiment of this invention in the accompanying drawings in which:

Fig. 1 is a side elevation of a photo-electric tubeembodying this invention;

Fig. 2 is an end elevation thereof; and

Fig. 3 is a detail sectional view through one of the anode mountings. I

One form of photo-electric tube is shown in Figs. 1 to 3, in which the tube is designated generally by the numeral 2| and has a cathode 23 mounted therein arranged 'to receive light through a side of the tube or through a window formed at a side thereof in the customary manner. The anodes are designated generally at 24, a multiplicity of which are mounted in an end of the tube 2!, as will be evident from Fig. 1.

I have shown the anodes 24 as formed by wires slightly spaced from each other, and fused together in glass beads 26, which form the end of the tube 2l.' The wires are arranged substantially in a bundle, and when fused in this way they provide a multiplicity of anodes fixed in the end of the tube and insulated from each other, as will be evident from Figs. 1 to 3. The size of these and the relative spacing thereof is appreciably exaggerated for clearness of illustration, it being evident that only fine wires are required and'closely spaced from each other, so that an appreciable bundle of wires per square inch may be used in a single tube.

The end of each wire forms a tiny anode surface facing the cathode 23, so as to receive electravel in parallel directions and in straight lines from the cathode to the anode, so as to be directed onto particular anodes according to the spotson thecathqde receiving light from the picture orpattern. Thusnot only will portions of the reproduced picture or other pattern be illuminated or depicted, but shadows and variations in shade will be reproduced also corresponding with those on the pattern. Therefore, it is necessary merely to have as large a number of anodes as is required to get the desired detail, which can be arranged conveniently and satisfactorily without the necessity for assembling a large number of separate and independent photo-electric tubes as has been required heretofore.

The form of tube here shown may be used These electric lamps corresponding with the spots on the cathode that may receive light, one lamp being energized for each spot of light directed on the cathode.

covering a substantial area, with a corresponding 1 Thus by arranging the lamps in a large bank' anode for each lamp, it is possible to reproduce:

on the lights many different pictures or other effects, or to use this principlein business .ma chines for sorting or tabulating from characters on film or papers Bycexpcsing afilm orpapcr to. the cathode, lainpsz corresponding with the spots thereof will be-ignitedand thepicture, film or the like will 'be .reprcduced. .in .the bank of lamps. The arrangement of the multiplicityeof anodes in association, with ,a. cathode causes the electron streams to travel in parallel directions from the cathode surfaceio thecorresponding anodes, thus making it possible to reproduce accurately the film,;pioture or the like, according to the spots of light applied tcthe cathode.

This arrangement makes it possible for the electrons fromany particular spoton the cathode to be directed to a corresponding certain anode. Since each anodeis connected in a separate and independent circuit, it may-have-adilferent cur.- rent from the others, Whereb dtcan cause a produce light and darlcshadows in thereproduced picture.

This principle is operable in many different systems, as for instance, itcanibeused for operating relays instead ofuzfor energizing incandescent lamps merely by making the proper substitution in the energizing. system. It may be .usedas a basis for an automatic tabulating-machine operated in -responseto codeor other cards photo-electric cellsheretofore required.

The tube maybe evacuated and the electrodes treated in the usual way of preparing a photo- .electric tube, particularly in preparing .theoathode to be lightresponsive.

While the invention has been illustratedand described in one embodiment, it is recognized that tively different portions of the cathode surface.

2. In a photo-electric. tube,,the v,oo rriloination' reproduction of light to-Varying. degrees, so as to or-film,replacing-the large number of individual along substantially. parallel lines from .respec- 4 with a cathode surface, of a plurality of anode surfaces arranged in cooperating relation with the cathode surface in position to receive electronic emission from the cathode surface along substantially parallel lines to the respective anode surfaces.

3. In a photo-electric tube, the combination with a cathode surface, of a multiplicity of anode surfaces arranged substantially parallel with the ,cathode surf-ace and in position to receive electronicemission therefrom along substantially parallel lines from the cathode surface to the respective anode surfaces.

4. In a photo-electric tube, a multiplicity of anodes comprising conductive elements having .spot anodesurfacesjthereon.

5. In a photo-electric tube, the combination with ga-cathode surface, of a plurality of anode surfaces comprising conductive elements each haying-an anode surface-thereon.

'6. A photo-electric tubecomprising an envelope having a cathode surface mounted therein, and a'pluralitypf anodes arranged incooperating relation with said cathode, eachof theanodescomprisin a wire having an. anode surface .directly thereon. e we l I 7, Aphoto-electrictubecomprisingan envelope having-a cathodesurf'ace mounted therein, and a plurality ofanodes. arranged incooperating relationavith said cathode, eaclrof. the anodes com.- prisin a wire having an. anode surface directly onthe end thereof.v

8. Aphoto-electric tube comprising anenvelope having a cathode surface mounted therein, and a plurality of anodes arranged in cooperating re.- lation with said cathodaeach of the anodes :comprising a wire-having. an .anode surface .on the endthereof, saidanode wiresbeing arranged. in a ,bundleand. respectively embedded in insulating material separating the wires from I each other and mounting the sameinthe envelope.

9. A photoeelectric tube comprising an envelope having a cathodesurface therein, a pluralitybf glass .beads arranged, in abundle in the envelope and fused together, a wire extending through each of the beads .and ,supportedthereby, means forming an anode surface on each of the .Wires in cooperating relation .with the. cathode surface.

10. A phcto electric. tubecornprising an envelope having av cathode surface therein, and a plurality of .wires extending in spaced parallel relation in the envelopeeach of the Wires having ;an anode surf-acedirectl on theend thereof circumscribed by ,theperiphery of the wire.

ORAN T. MCILVAINE.

REFERENCES GETED I The following references are of record ,in the fileof thispatent:

UNITED STATES PATENTS 

